Figure 1
From: Dendritic spine dynamics leading to spine elimination after repeated inductions of LTD
Induction of chemical LTD and establishment of long-lasting synapse reduction by repetitive inductions of chemical LTD.
(a) cLTD induced by exposure to DHPG (50 μM, 10 min). (b) Timeline of experimental procedures. The same dendritic segments were observed periodically using a confocal microscope. (c) Representative series of images. Each image is a reconstruction created by stacking images obtained at multiple focus planes, but we chose the segments running almost horizontally as possible. (d) Spine density as a function of number of days after repetitive induction of cLTD. The dendritic segments examined are 20 from 9 independent 3× mock cultures and 23 from 10 independent 3× cLTD cultures. P values are 2.3 × 10−7, for ***1, 1.4 × 10−10, for ***2 and 5.7 × 10−7 for ***3 in 2-factor factorial ANOVA (F(1,41) = 17.7, P = 1.4 × 10−4) followed by Bonferroni's test. Due presumably to an extended culture period and photodynamic damages, the spine density at PS day 20 was lowered. (e) The ineffectiveness of <3 × cLTD for synapse reduction as assayed at PS day 6 (4 days after the 3rd cLTD induction). The dendritic segments examined are 20, 17, 19, 23 from 9, 6, 9, 10 independent cultures for 0×, 1×, 2× and 3× cLTD induction groups, respectively. P values are 5.3 × 10−4 for ***4, 9.0 × 10−3 for **5 and 2.4 × 10−3 for **6 in one-way ANOVA (F(3,75) = 8.6, P = 5.5 × 10−5) followed by Bonferroni's test.
